Headers are typically used for electronic device packaging to provide stable and protective housing structures while providing electrical interconnections with associated pins for mounting and connecting to other devices. Certain operating conditions and environments can present a number of packaging challenges for reliable operation of the electronic devices. For example, pressure sensors that are utilized in aircraft engines, power generating turbines, or similar harsh and/or high-temperature environments are often subject to temperatures exceeding 400° C. In such devices and operating conditions, high-temperature headers and hermetic sealing can be utilized to increase the device reliability.
In general, headers for use with high-temperature pressure sensors can include mechanical housings and/or substrates with hermetic seals to accommodate various types of electrical interconnections and sensing elements. The need to maintain hermetic seals at elevated temperatures can present a number of challenges that require careful selection of materials, for example, to form a mechanically and electrically stable package.
Traditional headers utilize various metallurgical materials and plating that can have limitations at elevated temperatures. For example, traditional pin construction utilizes Kovar and/or Alloy 52 and nickel and/or gold plating. Such materials can limit the capability and reliability of the metal contacts formed between the sensing element and the metal pins in the header. Furthermore, the mechanical integrity of the header package is typically limited by the selection of material used to house the pins and to mount the sensing element. Typically available dielectric materials, such as Corning Pyrex, Corning 7052, Schott Borofloat, and similar borosilicate glasses, can undergo deformation at temperatures above 500° C., along with a degradation of their insulating properties.
In general, there is a need for increasing the reliability of the various interfaces between a pressure-sensing element, the measured environment, and the associated package for operation at increased temperatures.